Implantable connector

ABSTRACT

A connection system implantable within a living body having an exterior skin includes a male connector and a female connector. The male connector includes a shaft extending along an axis between a proximal end and a distal end, the shaft having an exterior surface surrounding the axis, at least one shaft contact carried on the shaft and exposed at the exterior surface, and a retaining element mounted to the shaft. The female connector includes a structure defining a bore extending along an axis between a proximal end and a distal end, at least one bore contact mounted to the structure and exposed within the bore and a catch element mounted to the structure. The catch and retaining elements allow the shaft to be inserted into the bore to align the contacts. A locking element rotatably locks the shaft in the bore. A method of implanting the system is also provided.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a divisional of patent application Ser. No.14/971,311, filed Dec. 16, 2015, entitled IMPLANTABLE CONNECTOR, and isrelated to and claims priority to U.S. Provisional Patent ApplicationSer. No. 62/093,208, filed Dec. 17, 2014, entitled IMPLANTABLECONNECTOR, the entirety of which is incorporated herein by reference.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

n/a

TECHNICAL FIELD

The present invention relates to an implantable connector for use with amedical device implanted within an animal; or, more particularly, foruse with an implanted ventricular assist device and system.

BACKGROUND

In certain disease states, the heart lacks sufficient pumping capacityto maintain adequate blood flow to the body's organs and tissues. Forexample, conditions such as ischemic heart disease and hypertension mayleave the heart unable to fill and pump efficiently. This condition,also called congestive heart failure, may lead to serious healthcomplications and even death. In fact, congestive heart failure is oneof the major causes of death in the Western world.

This inadequacy of the heart can be alleviated by providing a mechanicalpump also referred to as a ventricular assist device (“VAD”) tosupplement the pumping action of the heart. VADs may be used to assistthe right ventricle, the left ventricle, or both. For example, a VAD mayassist the left ventricle by mechanically pumping oxygenated blood fromthe left ventricle into the aorta. In this case, the pump is implantedwithin the body of the patient so that an inflow opening of the pumpcommunicates with the left ventricle, and an outflow opening of the pumpcommunicates with the aorta. The pump receives blood from the leftventricle and then pushes it into the aorta for distribution throughoutthe body. This reduces the strain on the heart by reducing the volume ofblood that the heart is responsible for moving. A VAD having an inflowopening communicating with the right ventricle and an outflow openingcommunicating with a pulmonary artery may be used to assist the rightventricle.

U.S. Pat. Nos. 7,575,423, 7,976,271, 8,007,254, and 8,419,609, thedisclosures of which are hereby incorporated by reference, disclosecertain rotary blood pumps which can be used as ventricular assistdevices. These pumps are electrically powered. Typically, these andother electrically powered implantable pumps are connected through acable, commonly referred to as a “driveline,” to a control device whichsupplies electric power to the pump and controls its operation. Thecontrol device is often external to the patient's body, in which casethe driveline must extend out of the body via a skin opening. Thecontrol device must usually provide continuous electric power over thedriveline. This power must be provided at relatively high current(0.5-2.0 Amps) and moderate voltage (3-40 Volts) for extended periods oftime, such as years or decades, without losing electrical continuity andcreating heat losses due to resistance that would cause physiologicalcomplications.

The driveline must withstand movement of the surrounding body tissuesand contamination by body fluids. Separable connectors generally havebeen regarded as not providing the requisite combination of currentcarrying capacity, reliability and durability in this demandingenvironment. The drivelines used heretofore typically have been made ascontinuous cables, without any separable connections at least in thatportion of the driveline that extends within the body of the patient.

Because any skin opening provides a natural means for bacteria or othercontaminants to enter the body, infections can occur at the skinopening. If such an infection occurs, then it may become necessary toremove or replace the driveline from the skin opening to permit propertreatment of the infection. Where the driveline is a continuous element,there is presently no way to effect these treatments without subjectingthe patient to a major surgery. Typically, a surgeon must remove theentirety of the existing driveline, including the portion adjacent theVAD, in order to route the new driveline through a new skin opening thatis remote from the infection.

It has also been proposed to use implanted control devices that receivepower from an external source by means of an implanted induction coil,without a permanent skin-penetrating connection. In such an arrangement,the control device and the entire driveline are disposed within thebody. It would be desirable to provide a separable connector at one orboth ends of such a driveline to facilitate threading of the drivelinethrough the body during installation.

Therefore, further need exists for improvements in drivelines andconnection systems.

SUMMARY

A first aspect of the present invention is a connection systemimplantable within a living body having an exterior skin. The systemincludes a male connector with a shaft extending along an axis between aproximal end and a distal end, the shaft having an exterior surfacesurrounding the axis, at least one shaft contact carried on the shaftand exposed at the exterior surface, and a retaining element mounted tothe shaft. The system further includes a female connector with astructure defining a bore extending along an axis between a proximal endand a distal end, at least one bore contact mounted to the structure andexposed within the bore and a catch element mounted to the structure.The catch and retaining elements are constructed and arranged so thatthe shaft can be inserted into the bore along the axis of the bore toalign the at least one shaft contact with the at least one bore contact.The shaft can be inserted in the bore in a first position in which theretaining element is offset from the catch element and retained in thebore when rotated about the axis of the bore into a second position inwhich the retaining element is aligned with the catch element. A lockingelement is mounted to one of the shaft and the structure, the lockingelement being movable between an unlocked position in which the shaftcan be rotated about the axis of the bore and a locked position in whichthe locking element prevents rotation of the shaft relative to thestructure.

In accordance with other embodiments of the first aspect, the bore maybe closed at its distal end and the male and female connectors may beconstructed and arranged to seal the bore proximal to the at least onebore contact when the shaft is inserted in the bore. The male and femaleconnectors may cooperatively define a sealed interior volume when theshaft is inserted in the bore, wherein the sealed interior volume is atleast about 1.10 times the volume of the shaft disposed within thesealed volume when the male and female connectors are fully engaged withone another. The structure may define an expansion space incommunication with the bore, and the expansion space may be at leastabout 0.05 times the total interior volume.

The catch element may include a catch ring with proximal and distalsurfaces extending at least partially around the axis of the bore, thecatch ring having at least one groove extending from the proximalsurface to the distal surface, and the retaining element may include atleast one projection extending away from the exterior surface of theshaft transverse to the axis of the shaft such that the at least oneprojection can be inserted through the at least one groove. The systemmay further include an anti-rotation element mounted to the structureand disposed distal to catch ring, the anti-rotation element configuredto engage the at least one projection to limit rotation of the shaftrelative to the structure. The structure may define a hole extendinginto the bore transverse to the axis of the bore, and the lockingelement may be engageable with the male connector through the hole tolock the shaft against rotation relative to the structure. The lockingelement may be a set screw and the hole may have a threaded wall, and adriving portion of the set screw may be covered by a set screw sealadapted to receive a tool engageable with the driving portion.

Either the shaft or the bore may have at least one seal adapted to sealthe bore proximal to the at least one bore contact when the shaft isinserted in the bore. The at least one shaft contact may include a firstset of shaft contacts spaced apart from a second set of shaft contactsalong the axis of the shaft and the at least one bore contact mayinclude a first set of bore contacts spaced apart from a second set ofbore contacts along the axis of the bore, wherein insertion of the shaftinto the bore along the axis of the bore aligns the first and secondsets of shaft contacts with the respective first and second sets of borecontacts. The system may further include an intermediate seal on eitherthe shaft or the bore, the intermediate seal being disposed between thefirst and second sets of shaft and bore contacts when the shaft contactsare aligned with the bore contacts. Each of the first and second sets ofshaft contacts the each of the first and second sets of bore contactsmay include three contacts. Either the shaft or the bore may have atleast one seal located between each mutually adjacent shaft or borecontact. The system may further include an implanted medical devicehaving first and second elements, the second element being sufficient tosustain life, and wherein the first element is connected to the firstsets of shaft and bore contacts, the second element is connected to thesecond sets of shaft and bore contacts. Each of the first and secondelements may be a pump having a motor.

The at least one shaft contact may be an outer ring and the at least onebore contact may be an inner ring, the inner ring being coaxiallyaligned with the outer ring when the male connector is inserted into thefemale connector. The system may further include an elongated conductorwith a terminus attached to each of the at least one bore contacts andthe at least one shaft contacts, wherein each terminus is welded to arespective swage cap that is conductively attached to the respectiveelongated conductor. Each of the at least one bore contacts may have aninterior surface with an annular groove and a spring element disposed inthe annular groove so as to conductively engage one of the at least oneshaft contacts.

A second aspect of the present invention is a connection systemimplantable within a living body having a thorax and an exterior skin.The system includes a first driveline extending between an implantabledevice configured to be located inside the thorax and a first connectorconfigured to be located at an internal connection point disposedoutside of the thorax, and a second driveline configured to extendthrough the exterior skin between an external device located outside thebody and a second connector that is configured to be releasably coupledto the first connector at the internal connection point so asoperatively connect the first and second drivelines, wherein the firstconnector can be decoupled from the second connector at the internalconnection point.

In accordance with other embodiments of the second aspect, the internalconnection point may be disposed outside of the pericardial sac. Theimplanted device may be a medical device having at least two partiallyredundant elements, each element being sufficient to sustain life,wherein each of the first and second connectors has a first set ofcontacts sealed independently from second set of contacts, and whereineach of the at least two partially redundant elements is powered by oneof either the first or second set of contacts. The second driveline maybe configured to extend between the second connector at the internalconnection point and a third connector adapted for mounting at the skin.

A third aspect of the present invention is a method of implanting aconnection system within a living body having a thorax and an exteriorskin, including implanting a device in the body and locating a firstconnector of a first driveline attached to the device at an internalconnection point disposed outside of the thorax, releasably coupling asecond connector of a second driveline to the first connector at theinternal connection point to operatively connect the first and seconddrivelines, and installing the second driveline so that a portion of thesecond driveline extends through the skin.

In accordance with other embodiments of the third aspect, the method mayfurther include the steps of releasably decoupling the first connectorfrom the second connector at the internal connection point, releasablycoupling a third connector of a third driveline to the first connectorat the internal connection point so as operatively connect the first andthird drivelines, and installing the third driveline so that a portionof the third driveline extends through the skin. The second drivelinemay extend through the skin a first exit point, and the third drivelinemay extend through the skin at a second exit point remote from the firstexit point.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the subject matter of the presentinvention and the various advantages thereof can be realized byreference to the following detailed description in which reference ismade to the accompanying drawings in which:

FIGS. 1A and 1B are front plan views of a male connector and a femaleconnector, respectively, of a connection system in accordance with oneembodiment of the present invention;

FIGS. 2A and 2B are front perspective and top plan views, respectively,of a shaft contact, an elongated conductor, and a swage cap of the maleconnector shown in FIG. 1A;

FIGS. 3A and 3B are front perspective and top plan views, respectively,of a male driveline interface of the male connector shown in FIG. 1A;

FIG. 4 is a front sectional view of a first driveline of the maleconnector shown in FIG. 1A;

FIGS. 5A and 5B are front plan views of different versions,respectively, of a proximal end of the male driveline interface shown inFIGS. 3A and 3B;

FIG. 6A is a front sectional view a proximal portion of the femaleconnector shown in FIG. 1B;

FIG. 6B is a front perspective view of a bore contact and an elongatedconductor of the female connector shown in FIG. 1B;

FIGS. 7A and 7B are front plan and front sectional views, respectively,of a bore contact, an elongated conductor, and a swage cap of the femaleconnector shown in FIG. 1B;

FIGS. 8A and 8B are front plan and side sectional views, respectively,of a primary seal used in connection with the female connector shown inFIG. 1B;

FIGS. 8C and 8D are front plan and side sectional views, respectively,of a secondary seal used in connection with the female connector shownin FIG. 1B;

FIGS. 9A and 9B are front sectional and bottom plan views, respectively,of a proximal end of the female connector shown in FIG. 1B;

FIGS. 10A-10C are bottom plan views of the female connector shown inFIG. 1B;

FIGS. 11A and 11B are front sectional views of different portions,respectively, of the male connector shown in FIG. 1A assembled with thefemale connector shown in FIG. 1B;

FIG. 12 is a front perspective view of a female connector in accordancewith another embodiment of the present invention;

FIG. 13 is a top plan view of a mold and components of the maleconnector shown in FIG. 1A;

FIGS. 14A-14C are front perspective, front plan, and front sectionalviews, respectively, of different stages during a method ofmanufacturing the female connector shown in FIG. 1B;

FIG. 15 is a front plan view of a connection system having an implantedmedical device in accordance with an embodiment of the presentinvention; and

FIG. 16 is a front plan view of a connection system having an implantedmedical device in accordance with another embodiment of the presentinvention.

DETAILED DESCRIPTION

FIGS. 1A and 1B illustrate elements of a connection system 10 that, forexample, may be an element of an implanted VAD system in accordance withthe present invention. As shown, system 10 includes a male connector 20that is mateable with a female connector 60. Male connector 20 isattached to a male or first driveline 11, while female connector 60 isattached a female or second driveline 15. Thus, system 10 conductivelyattaches, i.e., permits electricity to flow between, the first andsecond drivelines 11 and 15 once male connector 20 is received withinfemale connector 60. As described in detail below, male connector 20extends along an axis A-A, while female connector 60 extends along anaxis B-B. When the connectors 20 and 60 are engaged with one another,these axes are coaxial with one another. The designation BA-BA is usedin the drawings (e.g., FIG. 11A) to denote the coaxial axes A-A and B-B.

Male connector 20 has a shaft 22 extending along axis A-A between adistal end 24 and a proximal end 26. For simplicity, each of theproximal and distal directions have been labeled with a respective “P”and “D” arrow in the drawings to permit consistent use of those termswith respect to male and female connectors 20, 60 and the relatedmethods and systems described herein. Shaft 22 has an exterior surface23 surrounding axis A-A with a diameter sized for insertion into a bore62 (FIG. 6A) of female connector 60.

Shaft 22 has at least one shaft contact 30 carried on shaft 22 and atleast partially exposed at exterior surface 23. Although depicted ascircular, shaft contacts 30 may assume any number of geometric forms. Inthe depicted embodiment, each shaft contact 30 is a conductive ring,best seen in FIGS. 2A and 2B, with a diameter 30D. The remainder ofshaft 22 has a diameter equal to the diameter 30D of the shaft contacts.Shaft 22 may have a plurality of shaft contacts 30, spaced apart fromone another along axis A-A. In the depicted embodiment, shaft 22 has sixshaft contacts 30 that are spaced apart along axis A-A, each shaftcontact 30 being separated from the next adjacent shaft contacts by apotting material 19 discussed in detail below.

First driveline 11 is attached to a male driveline interface 28 locatedadjacent to proximal end 26 of shaft 22. Driveline 11 is a cable thatincludes at least one first elongated conductor 12, one of which isdepicted as broken lines in FIG. 1A. Each conductor 12 preferablyincludes a conductive core covered by a thin insulating layer. Forexample, each elongated conductor 12 may be a wire with a conductivecore made of silver. As shown in FIG. 4, first driveline 11 includes afirst exterior housing 14 that surrounds each first elongated conductor12 along at least a portion of its length. First exterior housing 14 ispreferably made of a flexible, implantable material, such as a materialderived from polyurethane, polyvinyl chloride, silicone, nylon, or otherbiocompatible material with like properties.

Each elongated conductor 12 extends from first driveline 11, throughmale driveline interface 28, and into the interior of shaft 22. A firstterminus 13 of each first elongated conductor 12 is adjacent to aparticular shaft contact 30, as best seen in FIG. 1A. Generally, eachconductor 12 extends co-directionally with axis A-A. Each shaft contact30 is conductively attached to one of the first elongated conductors 12within shaft 22. Preferably, each shaft contact 30 is made of a weldablematerial such as platinum, platinum-iridium alloy, or other conductivemetal that can be laser welded, resistance welded, or likewise fusedwith an elongated conductor 12. An exemplary first elongated conductor12 is depicted in FIG. 2A as being lap welded to an interior surface 33of shaft contact 30. To facilitate welding and mitigate corrosion risks,first terminus 13 of first elongated conductor 12 is covered with aswage cap 32 having a chamfered front face 37 and an elongated body 38.One swage cap 32 is crimped, swaged, welded, or otherwise conductivelyattached to each first elongated conductor 12. The metal of swage caps32 is selected for compatibility with shaft contacts 30. Preferably, aportion of elongated body 38 of swage cap 32 is lap welded to interiorsurface 33 of shaft contact 20, as shown in FIG. 2B. By virtue of thisconfiguration, swage cap 32 facilitates welding and mitigates thecorrosion risks associated with welding dissimilar metals, such as, forexample, the platinum of the contacts and the silver cores of theexemplary wires described above.

FIG. 1A also shows that each shaft contact 30 is at least partiallysurrounded on at least one side by a backfill or potting material 19.Preferably, potting material 19 has a high dielectric strength. Pottingmaterial 19 desirably is also an adhesive material capable of bondingwith each shaft conductor 30 to form shaft 22. For example, pottingmaterial 19 may be an epoxy, polymeric resin, or thermoplastic polymer,such as polyketone or like material. As described with reference to themethods of manufacture set forth below, potting material 19 ispreferably a flowable material selected to optimize the flexural andtensile strengths of male and female connectors 20, 60.

An exemplary embodiment of male driveline interface 28 is depicted inFIG. 3A. As shown, interface 28 is preferably a hollow, generallycylindrical element having an exterior surface 29 extending along axisA-A from an entry portion 34 to an annular ridge 40 that is adapted toengage driveline 11. Entry portion 34 is adjacent to the distal end ofmale driveline interface 28, and defines an internal diameter 34D. Maledriveline interface 28 defines a slightly smaller internal diameter 35Dat its proximal end, and a lip 35 at the juncture of diameters 35D and34D. Diameter 35D is sized to receive at least one first elongatedconductor 12 therein. For example, the smaller inner diameter 35D ofmale driveline interface 28 in FIG. 3B is approximately 3 to 6 mm andsufficient to house six elongated conductors 12 therein. Diameter 34Dsized to receive a guiding element 36 at proximal end 26 of shaft 22.Guiding element 36 is coaxial with shaft 22 and has an outer diameterapproximately equal to the outer diameter of shaft 22. Preferably,guiding element 36 is an elongated titanium ring engageable with acorresponding element of female connector 60 to guide shaft 22 into bore62, as described in detail below.

The distal end of male driveline interface 28 has a retaining portion 96located adjacent to proximal end 26 of shaft 22. FIG. 3B depicts anexemplary arrangement of retaining portion 96 having four retainingprojections 97. The retaining projections 97 are arranged in an array onexterior surface 29 of male driveline interface 28. In the embodimentdepicted, the projections 97 are spaced apart from one another about thecircumference of the driveline interface.

The proximal end of male driveline interface 28 is depicted in FIGS.5A-B as having a depression 39 and annular ridge 40. Depression 39 is anindented potion of exterior surface 29 that extends around axis A-Abetween a ledge 41 defined by an annular ridge 40. Annular ridge 40preferably has a triangular cross-section and defines a surface ofrevolution about axis A-A. For example, annular ridge 40 is shown inFIG. 5B as having a triangular cross-section with a height extendingaway from axis A-A. Alternatively, as in FIG. 5A, annular ridge 40 mayalso have a cylindrical portion 44. Ridge 40 of the male drivelineinterface 28 is adapted to engage exterior housing 14 of first driveline11. Preferably, the elements described above permit male drivelineinterface 28 to be securely engaged to exterior housing 14 to meetindustry standard requirements for tensile and flexural strength.

To provide additional tensile and flexural support, an overmold 42preferably covers the entirety of the proximal end of male drivelineinterface 28, including depression 39 and ridge 40. As shown in FIG. 4,overmold 42 tapers away from an edge portion 43 in the proximaldirection along axis A-A. As further discussed below, edge portion 43forms a seal with the female connector when the connectors are engagedwith one another. In addition, overmold 42 also mechanically supportsthe connection system by providing a means of strain relief for firstdriveline 11, and by compressively reinforcing the connection betweenmale driveline interface 28 and exterior housing 14 of first driveline11. Lastly, overmold 42 also provides male connector 20 with astreamlined exterior profile that is easily pulled through a surgicallyformed tunnel in the body during installation of the driveline.

The elements of male connector 20 set forth above may be assembled usingthe exemplary manufacturing method shown by FIG. 13. As shown, thismethod uses a mold 50 that is adapted to form shaft 22. The elements ofshaft 22, including shaft contacts 30 and driveline interface 28, arepositioned in a spaced apart arrangement within a main channel 51 ofmold 50. Each shaft contact 30 is conductively attached to at least onefirst elongated conductor 12, preferably using swage cap 32, prior toarrangement within mold 50. After all the elements of male connector 20have been attached and arranged, the potting material 19 (FIG. 1A) isguided into the spaces between the shaft elements of shaft 22 by aplurality of channels 52 on mold 50. Once guided into position, pottingmaterial 19 is cured into its final, relatively hardened state. Wherethe potting material is an epoxy or other chemically reactivecomposition, curing occurs by chemical reaction, with or withoutapplication of heat. Where the potting material is a thermoplastic,curing may occur by cooling of the potting material. Mold 50 preferablymakes the exterior surface of potting material 19 flush or nearly flushwith the exterior surface 31 of each shaft contact 30 so as to ensurethat diameter 30D is constant along shaft 22, as in FIG. 1A. To ensure asmooth exterior surface for optimum connection with female connector 60,exterior surface 23 of shaft 22 may subjected to a method of surfacetreatment that comprises, for example, the step of grinding or otherwisemachining the exterior surface 23 of shaft 22 until it has a constantdiameter 30D. This step may also provide a desired surface finish on theexterior surface 31 of each shaft contact 30, and to assure that thereis no potting material overlying the exterior surfaces of the shaftcontacts.

Female connector 60 has a structure 61 defining a bore 62 extendingalong an axis B-B between a distal end 64 and a proximal end 66, asshown in FIG. 1B and the corresponding sectional view FIG. 6A. Bore 62is open at proximal end 66 and closed at distal end 64. Structure 61 mayinclude an external housing 61 a shown in FIG. 1B, which is preferablymade of an implantable metal. Bore 62 of female connector 60 in FIG. 6Ahas an interior surface 63 surrounding axis B-B. Bore 62 preferably hasa diameter 62D sized to receive diameter 30D of shaft contact 30therein. At least one bore contact 70 is mounted in structure 61 andexposed to interior surface 63 of bore 62. Like shaft contact 30, borecontact 70 may assume any number of geometric forms. For example, as inFIG. 6B, bore contact 70 may be a conductive ring 70. Like maleconnector 20, female connector 60 may also have a plurality of borecontacts 70, each being spaced apart along axis B-B. In this example,FIG. 6A depicts a bore 62 having six bore contacts 70.

FIG. 1B also shows that a second driveline 15 is preferably attached toa female driveline interface 69 located adjacent to distal end 64 ofbore 62. In FIG. 11B, the proximal end of interface 69 is integral withstructure 61, although it could also be attached thereto. Similar toabove, the distal end of female driveline interface 69 also has adepression and annular ridge (not shown) similar to the depression 39and ridge 40 of the male driveline interface described above withrespect to FIGS. 5A and 5B. The second driveline 15 is also a cable thatincludes at least one second elongated conductor 16, one of which isdepicted as broken lines in FIG. 1B. Female driveline 15 preferably hasan exterior housing equivalent to exterior housing 14 of male driveline11 discussed above. The second driveline is engaged with the distal endof female driveline interface 69 in a manner similar to the engagementof the first driveline and the male driveline interface. Here again, anovermold similar to overmold 42 discussed above with reference to FIG. 4covers the second driveline and the interface. Each second elongatedconductor 16 extends generally co-directionally along axis B-B fromfemale driveline 15, through female driveline interface 69, and intostructure 61 until a second terminus 17 of each second elongatedconductor 16 is adjacent to a bore contact 70 within structure 61.

Each bore contact 70 is conductively attached to at least one secondelongated conductor 16. Preferably, like shaft contact 30, each borecontact 70 is also made of a weldable material such as platinum,platinum-iridium alloy, or like conductive metal that can be laserwelded, resistance welded, or likewise fused with an elongated conductor16. As an example, second elongated conductor 16 is depicted in FIGS. 7Aand 7B as being lap welded to an exterior surface 72 of bore contact 70.Like first terminus 13, second terminus 17 of second elongated conductor16 may be covered with a swage cap like swage cap 32. As above, aportion the swage cap may be lap welded to exterior surface 72 along aline parallel to axis B-B.

An interior surface 74 of each bore contact 70 may be optimized toconductively engage outer surface 31 of shaft contact 30. For example,interior surface 74 may be intentionally roughened to optimize itsconductive potential with exterior surface 31 of shaft 22. The exemplaryembodiment of FIGS. 7A-B has an interior surface 74 with an annulargroove 76 extending around at least a portion of diameter 62D of bore62. Annular groove 76 has a diameter 76D sized to receive a conductiveelement 78, such as conductive annular spring 78. As shown in FIG. 7B,diameter 76D is preferably greater than diameter 62D so as to defineannular groove 76. Conversely, conductive spring 78 preferably has adiameter 78D that is less than diameter 30D of shaft contacts 30. Byvirtue of this configuration, at least a portion of conductive element78 will remain conductively engaged with both shaft contact 30 and borecontact 70 when shaft 22 is inserted into bore 62. Likewise, whenembodied as annular spring 78, diameter 78D may also provide aninterference fit between shaft 22 and bore 62.

Bore contacts 70 may be secured in structure 61 by various means. Forexample, structure 61 may have a dielectric material defining aninternal surface that is adapted to receive a corresponding outersurface of each conductor ring 70. Preferably, as in FIG. 6A, adielectric potting material is utilized to form at least part ofstructure 61 and secure each bore contact 70 within bore 62. Preferablystill, potting material 19 fills substantially all any space withinstructure 61 that is not otherwise occupied by any of the elements orspaces of female connector 60 described herein.

The female connector further includes at least one seal 80 adapted toseal bore 62 when shaft 22 is inserted into bore 62. For example, inFIG. 6A, seven seals 80 are provided in the female connector. The seals80 include seals disposed between each pair of mutually-adjacent borecontacts 70, a seal 80D disposed distal to the bore contact 70 at thedistal end of the bore, and a further seal 80A disposed proximal to thebore contact 70 at the proximal end of the bore. Seal 80A is referred toherein as the proximal end seal. One of the seals 80C is referred toherein as a center seal. Center seal 80C is disposed between the thirdand fourth bore contacts, so that a first set 70A including three borecontacts 70 lies proximal to the center seal, whereas a second set 70Bincluding three bore contacts lies distal to the center seal.

Preferably, each seal 80 is a generally circular ring formed from a softa dielectric material such as silicone. The configuration of each seal80 is illustrated in FIGS. 8A-B, which depicts a seal 80 that has beenadapted to both seal bore 62 from immediate fluid ingress andcontamination and conductively insulate each bore contact 70 from thenext. For this purpose, each seal 80 preferably has an outer surface 82with a cross-section 83 shaped to have enhanced sealing capabilities.For example, outer surface 82 in FIG. 8B has an outer circumferentialsurface 84 opposite of an inner circumferential surface 85. Each ofthese surfaces 84 and 85 desirably is a surface of revolution about axisB-B, and each of these surfaces desirably has at least one undulation 86adapted prevent fluid entry into bore 62.

The female connector also includes a shaft receiving part 67 (FIGS.9A-11A) disposed at the proximal end of the female connector structure61. Shaft receiving part 67 is preferably made of a metallic material. Aretention means is also provided to retain shaft 22 within bore 62. Theretention means 90 includes a catch portion 91 on the shaft receivingpart 67 of the female connector 60 that is engageable with retainingportion 96 (FIGS. 3A and 3B) of male connector 20. As shown in FIG. 9A,the shaft receiving part 67 defines a generally cylindrical interiorbore 68 coaxial with bore 62 and with axis B-B. A catch portion in theform of a catch ring 92 projects inwardly toward towards axis B-B fromof the wall of bore 68. Catch ring 92 is subdivided by grooves 94 into aset of four catch projections 93 extending inwardly toward axis B-B todefine; with a groove 94 disposed between each pair of adjacent catchprojections 93. Grooves 94 extend entirely through the catch ring 92 inthe proximal-to-distal direction, and thus extend between the proximalfaces 95B and distal faces 95A of catch projections 93. Catchprojections 93 define a minor diameter smaller than the diameter of bore68. The minor diameter defined by catch projections 93 is smaller thanthe major diameter D₉₇ defined by projections 97 on the retainingportion of the male driveline interface (FIG. 3B). However, the minordiameter defined by projections 93 is slightly larger than the minordiameter D₉₆ of retaining portion 96. The major diameter at grooves 94is slightly larger than the major diameter D₉₇ defined by theprojections on the retaining portion of the male driveline interface.

Catch ring 92 is adapted to correspond with retaining portion 96 of maleconnector 20. For example, grooves 94 and catch projections 93 arepreferably spaced apart around the circumference of catch ring 92 sothat the spacing of grooves 94 corresponds with the spacing of retainingportions 97 (FIG. 3A) on retaining portion 96 of male connector 20. Asnoted above, retaining portion 96 is preferably located adjacent toproximal end 26 of shaft 22. The exemplary embodiment of FIG. 3A depictsretaining portion 96 as having four retaining projections 97, equallyspaced about the circumference of male driveline interface 28. The bore68 in shaft receiving part 67 includes a clear space distal to catchring 92 and projections 93 with a depth 68D along axis B-B. Depth 68Ddesirably is greater than greater than the axial extent of projections97 on the male driveline interface (FIG. 3B). The distal end of the boreis defined by a proximal spacer 102 having an opening 101 coaxial withbores 62 and 68 and sized to receive guiding element 36 of maleconnector 20 described above. The shaft receiving part 67 thus definesan annular shape or rotation path between the distal facing surface 95Aof catch projection 93 and proximal spacer 102. As shown in FIG. 10A,catch retaining part 67 also has an anti-rotation element in the form ofa pin 63A projecting into this rotation path 68. Anti-rotation element63A may have a chamfered edge.

The proximal boundary of bore 62 is defined by the proximal spacer 102.The distal end of bore 62 is defined by a distal spacer 100 (FIGS. 6Aand 11B). In some embodiments, spacers 100 and 102 may be spaced apartalong axis B-B so as to impart a compressive force on bore contacts 70and seals 80. Because each seal 80 is preferably compressible, thisforce may serve to maintain each bore contact 70 and seal 80 in a fixedposition along axis B-B when potting material 19 is applied.

Distal spacer 100 defines an expansion space 104. (FIG. 11B) Expansionspace 104 is in communication with bore 62 via a distal spacer opening105 within distal spacer 100. Distal spacer opening 105 preferably has adiameter 105D equal or less than diameter 30D of shaft contacts 30. Asdescribed above, at least one seal 80 is adapted to seal bore 62proximal to bore contact 70 when shaft 22 is inserted in bore 62.

The shaft-receiving part 67 of the female connector has a threaded hole112 extending transverse to the bore 68 of the shaft-receiving part andtransverse to the axis B-B. A locking element 110 in the form of a setscrew is threaded engaged in the hole. Set screw 110 has a tapered tip113 at one end and a driving portion 114 with a tool receiving recess115 shaped to receive a driving tool such as an Allen wrench therein. Byturning the set screw 110, the set screw or locking element can be movedbetween a retracted position depicted in FIGS. 10A and 10B in which theset screw does not project into bore 68 and an engaged position, shownin FIG. 10C, in which the tip 113 of the set screw projects into thebore.

A resilient seal 116 is provided at the end of hole 112 on the exteriorsurface of the shaft-receiving part 67. Seal 116 is adapted to permitaccess by a tool to the set screw during the process of engaging themale and female connectors, but to prevent fluid entry into hole 112after the connectors are engaged with one another. For example, seal 116may be a resilient element having a slit adapted to receive the drivingtool through the slit and then resiliently re-seal hole 112.

A method of manufacturing female connector 60 is depicted in FIGS.14A-C. The method uses a female assembly rod 130 having an elongatedshaft portion 131 projecting from an interface portion 134. As shown inFIG. 14A, shaft portion 131 preferably has a diameter approximate todiameter 30D of shaft contacts 30 and length greater than that of bore62. This exemplary method comprises the steps arranging the variouselements of female connector 60 on rod 130 as shown in FIG. 14B. Thediameter of shaft portion 131 may vary along its length. For example, inFIG. 14A, shaft portion 131 has a distal end 132 sized for insertioninto distal spacer opening 105 of distal spacer 100, and a proximal end133 sized for insertion into the bore of the shaft receiving element 67and the opening of proximal spacer 102. This configuration desirablypermits shaft portion 131 to support each element of female connector 60during assembly. Furthermore, this configuration also ensures that eachelement of female connector 60 is coaxially aligned along axis B-B. Thedistal end 132 of the shaft also has a catch 135 which can releasablyengage the distal end spacer 100 and hold it in place.

The bore contacts 70 and seals 80 are arranged on the shaft portion 131between the distal and proximal spacers 100 and 102. The dimensions ofthe shaft are selected so that spacers 100 and 102 impart a compressiveforce on bore contacts 70 and seals 80. Aside from ensuring that eachrespective element of female connector 60 remains in a fixed positionwith respect to rod 130, this step also prevents potting material 19from entering bore 62. Each bore contact 70 is conductively attached toa respective second elongated conductor 16 as discussed above, before orafter placement on the rod 130. The conductors are omitted in FIGS.14A-14C for clarity of illustration. Next, a hollow exterior housing 61a is placed over the elements that have been assembled on rod 130. Thiscreates a void space between the outer surfaces of bore contacts andseals 70, 80, and the interior surfaces of hollow housing 61 a, with theconductors disposed in the void space. Preferably, the assembly at thisstage includes means for accessing this void space. For example, thehousing or one of the other parts may have an access port (not shown) incommunication with the void space. As in FIG. 14C, potting material 19is then used to fill substantially all of the void space via the accessport and then cured, thereby sealing and mechanically uniting thevarious elements of female connector 60 to form the structure 61. Aftercuring, female driveline interface 69 (FIG. 11B) is attached and rod 130is removed. During introduction of the curing material, the seals 80compressed between the bore contacts and other elements block passage ofthe potting material to the inner surfaces of the bore contacts, andassure that the bore of the finished connector is free of pottingmaterial.

In a method of engaging the male and female connectors, the shaft 22 ofthe male connector is inserted through the bore 68 of theshaft-receiving part 67 and into the proximal end of the bore 62 in thefemale connector. As the distal end of the shaft 22 reaches the proximalend seal 80A, the shaft sealingly engages the proximal end seal. At thisstage, the male and female connectors cooperatively define a sealedvolume which includes all of the space within the bore 62 distal to theproximal end seal, and which also includes the space 104 (FIG. 11B) inthe distal spacer 102. This sealed volume is initially filled with airat atmospheric pressure. As the shaft 22 of the male connector continuesto advance into bore 62, the shaft occupies a progressively greaterportion of the space within the sealed volume and the air within thesealed volume is compressed. The compressed air acts on the shaft andcreates a force opposing further insertion. When the shaft is fullyadvanced, the final absolute air pressure P_(F) in the sealed volumewill be approximately:

P _(F) =P _(A)*(V _(SV))/(V _(SV) −V _(SH))

Where:

P_(A) is atmospheric pressure;

V_(SV) is the volume within the sealed volume; and

V_(SH) is the volume of the shaft which is inserted into the sealedvolume, i.e., the volume of the shaft which lies distal to the proximalend seal 80A when the shaft is fully inserted. Because the sealed volumeV_(SV) is larger than V_(SH), the air pressure does not reach extremelevels. V_(SV) can be sized to provide any desired value of finalpressure P_(F). For example, ISO27186, an international standard formedical device connectors, specifies a maximum insertion force of 16N or3.59 lb-f. For an embodiment of shaft 22 having a diameter of about 3mm, a pressure of 288 lb/in² corresponds to a force of 16N exerted bythe compressed air to provide a final pressure P_(F) less than this.Thus, the value of (V_(SV)−V_(SH)) must be at least 1.05 times V_(SH).Larger values of V_(SV) are also possible, such as at least 1.0 timesV_(SH), or at least about 1.2 to 1.3 times V_(SH), to provide even lowerpressure values.

During insertion, the locking element 110 is in the retracted positionshown in FIG. 10A, where the locking element is clear of the bore 68 inthe shaft-receiving piece 67 of the female connector. The axes of themale and female connectors are coincident, and lie along common axisBA-BA. The male connector is brought to a first rotational positionabout the axis relative to the female connector. In this firstrotational position, depicted in FIG. 10A, the projections 97 on themale interface adaptor, which constitute the retaining elements of themale connector, are out of alignment with the projections 93 of thefemale connector, which constitute catch elements. In this firstposition, the retaining elements or projections 97 are aligned with thegrooves 94 of the female connector. While the connectors are in thisfirst rotational position, the male connector is advanced distally toits fully-inserted position. The retaining elements or projections 97pass through grooves 94, from the proximal side of the catch elements orprojections 93 on the female connector to the distal side of projections93.

Once the male connector has reached this position, the male connectorcan be rotated relative to the female connector, as indicated by arrow Rin FIG. 10B, until it reaches the second rotational position shown inthis figure. In the second rotational position, the retaining elementsor projections 97 of the male connector are aligned with the catchelements or projections 93 of the female connector. A proximal facingsurface 98B of each retaining element 97 (FIGS. 3A and 4) confronts adistal facing surface 95A of each catch element 93 (FIGS. 9A and 4) whenshaft 22 is in the second position. At this point, shaft 22 is retainedin bore 62 by the interaction of retaining elements 97 and catchelements 93. Anti-rotation element 63A ensures proper alignment ofretaining elements 97 with catch elements 93 by stopping rotation of themale connector at the second position.

Locking element 110 may be engaged once shaft 22 is in the secondrotational position. As shown in FIG. 10C, the locking element orsetscrew 110 projects into the bore when the locking element is in theengaged position. As best appreciated with reference to FIG. 4, thelocking element 110 is aligned, along the common axis BA, with retainingportion 96 of male connector 20 and with projections 97 on the maleconnector. Rotation of the male connector in the reverse direction(opposite to arrow R in FIG. 9B) is blocked by interference between thelocking element 110 and the retaining elements or projections 97. Themale connector is thus securely locked against withdrawal from thefemale connector. Set screw 111 may be tightened sufficiently tofrictionally engage tip 113 with retaining portion 96. Importantly,however, the connectors remain securely locked even if tip 113 is notfrictionally engaged as long as tip 113 lies within the rotation path ofthe projections. In this configuration, retention means 90, includingthe retaining elements 97 and catch elements 93, prevents anysubstantial translation of shaft 22 along axis BA-BA, while lockingelement 100 prevents any substantial rotation of shaft 22 about axisBA-BA.

When the male connector is in its fully advanced position, each shaftcontact 30 is engaged with one bore contact 70 so that the wires of thefirst and second drivelines are conductively connected to one anotherthrough the engaged connectors. Also, the seals 80 sealingly engage theshaft 22 of the male connector. In this fully engaged condition, guidingelement 36 of the male connector is engaged in the opening 101 of theproximal spacer 102 in the female connector. (See FIG. 11A) so that theguiding element helps maintain concentricity of the shaft 22 and bore62. Also, in the fully engaged condition, the edge 43 of the overmold 42on the male connector (FIG. 4) abuts the shaft-receiving piece 67 of thefemale connector to form a seal.

The connectors 20, 60 can be used as elements of an implanted system. Asystem 10 is described below as a further embodiment of the invention.System 10 is depicted in FIG. 15 has having an implanted medical device140, such as a ventricular assist device or VAD device 140. In thisembodiment, device 140 has two elements which are at least partiallyredundant. For example, the VAD device 140 of FIG. 15 includes a firstset of electrical coils schematically indicated at 142A and a second setof electrical coils schematically indicated at 142B. The first set ofcoils is arranged to drive a first rotor (not shown) within the device140, whereas the second set of coils is arranged to drive a second rotor(not shown) within the device 140. In normal operation, both rotorsoperate. However, the VAD device 140 will still pump enough blood tokeep a patient alive even if only one rotor is operational. VAD device140 is connected to male connector 20 through the first driveline 11.Most preferably, the first redundant element (coil set 142A) isconnected by certain conductors in first driveline 11 to the first set30A of the shaft contacts 30 disposed adjacent the proximal end 26 ofshaft 22 of male connector 20 (FIG. 1A). The second redundant element142B is independently connected through other conductors of the firstdriveline 11 to the second set of shaft contacts 30B disposed adjacentthe distal end 24 of shaft 22. The assembly of the implantable device140 and the first driveline 11 may include a permanent or semi-permanentconnection between device 140 and driveline 11 that is formed by themanufacturer or made by any suitable method before or during theimplantation procedure discussed below.

The system 10 further includes a source of electrical power, such asexternal controller 150. Controller 150 desirably includes redundantcircuits such as a first drive circuit 152A arranged to supplyelectrical power to the first set of coils 142A and a second drivecircuit 152B arranged to supply electrical power to the second set ofcoils 142B. Controller 150 is connected to the female connector 60 bysecond driveline 15. Desirably, the first circuit 152A is connected tothe first set 70A of the bore contacts 70 (FIG. 6A) adjacent theproximal end 66 of the bore 62, whereas the second circuit 152B isconnected to the second set 70B of bore contacts adjacent the distal end64 of bore 62 and distal to the center seal 80C.

VAD device 140 is implanted within a living body 120 such as a humanbody 120 having a thorax 122 and an exterior skin 123. As is commonlyunderstood, the thorax 122 includes any portion of human body 120 thatis situated between the neck and the abdomen, and supported by the ribs,costal cartilages, and sternum. Heart 121 of body 120 is containedwithin a pericardial sac contained within of thorax 122. VAD device 140is implanted in body 120, preferably in close proximity to heart 121 andwithin the thorax 122. In some embodiments, device 140 is adjacent heart121 and within the pericardial sac. Once device 140 is implanted, maleconnector 20 may be located at an internal connection point 129 disposedaway from heart 121. Preferably point 129 is at least outside of thepericardial sac, or even outside of thorax 122. Female connector 60 maybe located at the internal connection point 129 by any known means. Forexample, female connector 60 may be pulled through a surgically-formedtunnel through body 121 to arrive at internal connection point 129.Second driveline 15 is implanted so that the female connector 60 is alsopresent at the internal connection point 129, and so that the seconddriveline 15 extends through the exterior skin 123 of body 120 at a skinopening 123A. Desirably, the internal connection location 129 is closeto skin opening 123A, but not directly at the opening.

In FIG. 15, female connector 60 is releasably coupled to male connector20 at internal connection point 129 so as to operatively connect firstand second drivelines 11, 15 outside of the thorax 122. The connectorsare locked together as discussed above. Once this connection is made,and preferably locked via locking element 100, external device 130 isoperationally connected to the implanted device 120 via a compositedriveline formed by connecting the first and second drivelines 11 and 15at internal connection point 129. The surgical openings used forimplantation and for access to connection site 129 are closed.

Advantageously, should skin opening 123A become infected, the infectioncan be remedied by a minor surgical procedure. Connection point 129 isaccessed to expose the connectors 20 and 60, which are thendisconnected. A new third driveline (not shown) with a new femaleconnector is connected to implanted male connector 20 at point 129. Thenew driveline is routed through the skin and out of body 120 at a newskin opening that is remote from the now infected skin opening 123A.Advantageously, this procedure can be performed without entering thethorax 122 (or the pericardium sac, depending upon the location of point129). In comparison to the operation which would be required to replacethe entire composite driveline, this constitutes a relatively minorsurgery. For example, the exemplary method set forth above does notrequire any re-tunneling of first driveline 11 through the body 120.

Connectors 20 and 60 also provide a significant safety benefits. Asmentioned above, the second set of bore contacts 70B (FIG. 6A) aredisposed distal to the center seal 80C. When connectors 20 and 60 areassembled, the second set of shaft contacts 30B is aligned with thesecond set of bore contacts 70B, so that the connections between thesecond sets of bore and shaft contacts, 30B and 70B respectively, arealso distal to the center seal 80C. In normal operation, the proximalend seal 80A excludes body fluids from the entire bore, so that all ofthe connections between the each of the first and second sets ofcontacts 30A, 70A and 30B, 70B remain functional. If the proximal endseal 80A fails, one or more of the connections between the first set ofcontacts 30A, 70A may fail. Consequently, the first set of coils 142A inthe VAD device 140 may cease to operate or may operate at reducedefficiency. The second set of coils 152B, however, will remainfunctional so that VAD device 140 can provide enough blood flow to keepthe patient alive. Moreover, the failure of coils 142A may be detectedby appropriate monitoring circuitry in external controller 150 so thatthe patient can seek attention to correct the failure. In the particularembodiment depicted, where there are further seals 80 between theproximal end seal 80A and the center seal 80C, these additional seals 80provide still further safety. For example, these additional seals 80, aswell as the center seal 80C, also must fail before the second set ofcontacts 30B and 70B will remain fail. Therefore, VAD device 140 maycontinue to sustain life, even if seal 80A fails, by drawing power fromsource 150 via the second set of contacts 30B, 70B.

The features discussed above can be varied without departing from thepresent invention. Some of these variants are discussed separatelybelow. However, the elements of any of these variants and alternateembodiments might also be incorporated into any embodiment of anyconnector, method or system described anywhere in the text of thisapplication.

In the system discussed above with reference to FIG. 15, the maleconnector 20 may be coupled to the controller 150 and the femaleconnector may be coupled to the implanted device 140. Although describedwith reference to an exemplary VAD device 140, connectors 20 and 60 canbe used to provide power or signals to or from an implanted device ofany nature. In the VAD embodiment discussed above, the first and secondcoil sets 142A and 142B 120 b are redundant, in that either element cansustain life. However, the elements connected through the first andsecond sets of contacts 30A, 70A and 30B, 70B need not be redundant. Forexample, the second set of contacts 30B, 70B may be connected to anessential element of a device, whereas the first set of contacts 30A,70A, which are adjacent the proximal end 66 of the bore 62, may beconnected to a non-essential element such as a monitoring or controlsystem.

In some embodiments, the elements of the retention means may be adaptedto provide a means for keying a particular male connector to aparticular female connector. For example, the catch ring 92 (FIG. 9A)may have a shape that is only engageable with a correspondingly shapedretaining portion 96 (FIG. 3A). By way of example, the catch rings ofsome female connectors may be made with catch rings having threeequally-spaced projections 93 and three grooves 94, and thecorresponding retaining portion 96 may have three equally-spacedprojections 97. Still other variants can have unequally spacedprojections and grooves in unique patterns. This is useful in assuringproper connections where there are multiple interconnects in any givensystem. The keyed shapes may be defined exclusively by the geometricarrangement of grooves 94 about the axis. Alternatively, one or more ofthe retaining projections and grooves may be of different sizes orshapes, so that it will fit only a correspondingly-shaped groove.

In the embodiments discussed above, the projections or catch elements 93on the catch ring have distal surfaces 95A (FIG. 9A) which do not slopein the axial direction. However, the catch elements may have surfacesdefining a portion of a helix about the axis B-B, so as to definecomplete or partial screw threads. Here again, the mating retainingelements 97 (FIG. 3A) may also have helical surfaces.

In the embodiments discussed above, the locking element or set screw 110(FIGS. 9A-9B) moves radially towards the axis as it is moved from itsretracted position to its advanced position. However, the lockingelement may move in other directions, such as directions parallel to theaxis. Also, the locking element need not be a screw. For example, thelocking element may be a pin, and may be held in its advanced or lockingposition be another element. Also, the seal associated with the lockingelement may be omitted or may be varied.

The swage caps 32 (FIGS. 2A and 7A) may be omitted where the metal ofthe wires is compatible with the metal of the contacts, so as to allowdirect welding. Alternatively, the swage caps can be replaced by jumperwires. In this embodiment, one end of each jumper wire is conductivelyattached to a contact 30 or 70, while the opposite end of the jumperwire is conductively attached to terminus 13 or 17 of first or secondelongated conductors 12 or 16 at a point remote from the respectivecontacts 30 or 70.

The connectors need not be attached to drivelines as discussed above.For example, as shown in FIG. 12, a female connector 140 has a structure141 that is integral with a portion of an implantable device 148, suchas header 143. Header 143 may be adapted to embody any or all of thefeatures and capabilities of structure 61 discussed herein. For example,an exemplary connection system 10 might include an implantable device148 with a bore 142 housed within header 143. FIG. 12 also demonstratesthat header 143, or any embodiment of structure 61 for that matter, mayalternatively be adapted to include a first bore 142A adapted to receivea first shaft 22A and a second bore 142B adapted to receive a secondshaft 22B.

A variety of seals may be utilized. For example, a female connector mayincorporate two different types of seals a primary seal equivalent toseal 80, as shown in FIGS. 8A-B; and a secondary seal 87, as shown inFIGS. 8C-D. The secondary seal may be thinner and may be less resistantto leakage than the primary seal. The primary seal may be provided atthe proximal end of the bore, whereas secondary seals may be used atother locations distal to the primary seal. In a variant of thisapproach, a primary seal is also used at a location between differentsets of contacts, so as to provide enhanced reliability in the event ofprimary seal failure. In a variant of this approach, the secondary sealsmay be replaced by dielectric washers which separate adjacent contactsfrom one another but which do not seal against fluid leakage along theshaft. Such washers may seal against entry of the potting materialbetween the bore contacts during the manufacturing process discussedabove with reference to FIGS. 14A-14C. In a further variant, themanufacturing process can be varied so that potting material 19 mayalternatively extends between adjacent bore contacts so as to eliminatethe need for separate seals or washers between the bore contacts. Thiswould require measures during the manufacturing process to avoidcontamination of the interior surfaces of the bore contacts by thepotting material. Alternatively still, potting material 19 may beutilized to define the boundaries of expansion space 104.

In the embodiments discussed above, the seals are carried on thestructure of the female connector. However, some or all of the seals maybe carried on the male connector as, for example, as O-rings surroundingthe shaft.

The varied connection types of connection system 10 also permitoptimization of connector type, either male or female, with device type.For example, any system or method employing connection system 10 may beadapted provide the less replaceable, more critical device with maleconnector 20 as it is easier to clean than female connector 60 in theevent it becomes contaminated during placement or use.

Multiple sets of connectors 20 and 60 may also be deployed within asystem 210 that, as shown in FIG. 16, includes an implantable controller250. Much like external controller 150, the implantable controller 250has a first set of circuits 252A and a second set of circuits 252B. Asbefore, first and second drivelines 11 and 15 are attached by connectors20 and 60 to form a first composite driveline. This allows controller250 to power the first set of circuits 252A with the first set ofcontacts 30A, 70A and the second set of circuits 252B with the secondset of contacts 30B, 70B. In contrast to above, however, implantablecontroller 250 is also connected to an external device or power source150 by a second composited driveline form by connecting first and seconddrivelines 211 and 215 at an internal connection point 229 using maleand female connectors 220 and 260. Connectors 20 and 60 are identical toconnectors 220 and 260, except in the 200 series of numbers. Therefore,the benefits described above with reference to FIG. 15 may be furtherextended in system 210. For example, the second driveline 215 may alsobe replaced with a new third driveline (not shown) during a minorsurgical procedure because driveline 215 also exits through the skinopening 123A in a similar manner to driveline 15. As a further example,the first and second circuits 252A, 252B of controller 250 can be alsopowered with a corresponding set of first and second set of contacts230A, 270A and 230B, 270B within connectors 220 and 260. Aside fromthese redundancy benefits, this configuration also allows implantablecontroller 250 to be easily replaced or upgraded to enhance patientsafety. For example, each internal connection points 129 and 229 may beadjacently located outside of thorax 122 so that implantable connector250 can be removed in a single procedure, preferably using commonsurgical opening.

In a further variant, the connections discussed above can be used tomake internal connections within a system that is entirely implantedunder exterior skin 123, thereby eliminating the need for skin opening123A. For example, connectors 20 and 60 may be used to connect device140 to implanted controller 250, as in FIG. 16, while connectors 220 and260 are used to connect controller 250 to another power source. In sucha system, for example, controller 150 may be powered by a transcutaneousenergy transfer coil or TET coil that is implanted beneath skin 123 atsome point in body 120. Once implanted, the TET coil is adapted toreceive power from an external coil adjacent skin 123. Because there isno skin opening 123A, the risk of infection in this alternate system isreduced. Nonetheless, by connecting the TET coil to the implantedcontroller 250 with connectors 220 and 260 at an internal connectionpoint like points 129 or 229 described above, similar benefits can berealized. For example, the system controller 250 may be redundantlyconnected to the TET coil, which, like controller 250, may also beeasily replaced as part of relatively minor surgical procedure.

Although the invention herein has been described with reference toparticular embodiments, it is to be understood that these embodimentsare merely illustrative of the principles and applications of thepresent invention. It is therefore to be understood that numerousmodifications may be made to the illustrative embodiments and that otherarrangements may be devised without departing from the spirit and scopeof the present invention as defined by the appended claims.

What is claimed is:
 1. A method of implanting a connection system withina living body having a thorax and an exterior skin, comprising:implanting a device in the body and locating a first connector of afirst driveline attached to the device at an internal connection pointdisposed outside of the thorax; releasably coupling a second connectorof a second driveline to the first connector at the internal connectionpoint to operatively connect the first and second drivelines; andinstalling the second driveline so that a portion of the seconddriveline extends through the skin.
 2. The method of claim 1, furthercomprising the steps of: releasably decoupling the first connector fromthe second connector at the internal connection point; releasablycoupling a third connector of a third driveline to the first connectorat the internal connection point so as to operatively connect the firstand third drivelines; and installing the third driveline so that aportion of the third driveline extends through the skin.
 3. The methodof claim 2, wherein the second driveline extends through the skin at afirst exit point, and wherein the third driveline extends through theskin at a second exit point remote from the first exit point.